1. Field of the Invention
The present invention relates generally to square bale forming apparatuses and, more particularly, to a cleanout assembly for cleaning interior regions of a plunger of a square bale forming apparatus which might otherwise become congested with materials that would be carried upward by knotting needles and become entangled in an overhead knotting device.
2. Discussion of the Prior Art
A square baler having plunger cleanout means is known from U.S. Pat. No. 4,829,756, issued on May 16, 1989, and assigned to the assignee of the present invention. The baler apparatus illustrated in U.S. Pat. No. 4,829,756, is substantially similar to the general type of baler with which the present invention is to be employed and, therefore, the disclosure of U.S. Pat. No. 4,829,756 is hereby expressly incorporated herein by reference.
The known plunger cleanout means basically includes a plurality of probes for clearing crop materials from clearance openings in a plunger head of the baler so that an apparatus, such as a curved needle, may pass up through the clearance openings without hinderance. The probes are mounted between a pair of drive arms of the baler for shiftable movement relative to the plunger head along a path of sweeping motion within the head during at least a portion of the operating cycle of the plunger head.
By this construction, the probes of the known plunger cleanout means provide a cleaning of the clearance openings between the plurality of crop engaging elements of the plunger head by moving along an arcuate path defined by the axis of rotation of the drive arm relative to the plunger head.
Although the known plunger cleanout construction performs the desired function in many diverse conditions under which the known baler may operate, it is possible in certain conditions for material to become lodged in the clearance openings between the crop engaging elements of the plunger head in and around a lower frame member of the plunger head in such a way that the probes, moving along the arcuate lines defined by the axis of rotation of the drive arm, are unable to clear the crop material sufficiently from around the frame member. In such circumstances, the crop material may build up in the clearance openings to a size sufficient to cause bending or breaking of the needles passing up through the openings during tying of the bale in the chamber or may be carried with the needles up into the knotting device.
It would be desireable to provide a plunger cleanout assembly which reliably cleans the clearance openings in a plunger head during operation of the baler under any conditions encountered so that the baler may be used in a wide variation of environments without experiencing problems with the tying needles carrying material into the knotting device or becoming bent or broken by crop material lodged in the clearance openings.